<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<script type="text/javascript">
			var m = "3";
			var n = 3;
			if (m == n) {
				console.log("m==n");//值相等			
			}
			if (m === n) {
				console.log("m===n");//值一样，但是类型不一样		
			}
			var sp = d.get;
			sp.innerHTML = 4;
		</script>
	</head>
	<body>
		<span id="sp">fggfg</span>
	</body>
</html>
